source strength of fitted dipole in source space

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1

Hi,

I am trying to model the influence of a (in mne_analyze) fitted dipole
to an existing measurement. The aim is to subtract the influence of the
dipole from the measurement in the sensor space.

The dipole fit delivers the location and the orientation of the
dipole. The orientation per room direction is expressed in nA. I now
calculate the forward solution by multiplying the dipole with the
leadfield to get the influence in the sensor space which is then
subtracted from the actual measurement.

My question concerns the source strength of the dipole: is it
necessary to normalize the source strength of the dipole (sqrt(Qx^2 =
Qy^2 + Qz^2)= Q = 1) or do I just use the strength per room direction
from the fit to define the activity of the dipole per direction?

Thanks a lot for your opinion,

Tim

2

hi Tim,

if you have the source amplitude and orientation then you can get the M/EEG
estimates but matrix multiplication with the forward solution a.k.a.
gain matrix.
See the simulation module in mne-python:

https://github.com/mne-tools/mne-python/blob/master/mne/simulation/evoked.py

HTH
Alex